Wireless-telegraph receiving device.



J.S.STONB.

. PATENTED UG.16,190

WIRELESS TELEGRAPH RECEIVING DEVICE.

APPLICATION FILED AUG. 11, 1902.

2 SHEETS-SHEET 1.

No. 767,971. .7 7 PATENTED AUG. 16, 1 904.

J. s. STONE. WIRELESS TELEGRAPH RECEIVING DEVICE.

APPLICATION FILED AUG.11, 1902.

I NO MODEL. 2 SHEETS-SHEET 2- \A/JTHEEEEIS; lH\ E:"\]Tm= UNITED STAT-13s;

Patented August 16, 190 1.

PATENT JOFFIICEO WIRELESS-TELEGRAP RECEIVING DEVICE.

SPECIFICATION forming art of Letters Patent No. 767,971, dated August 16, 1904.

Application filed August 11, 1902.

To all whom it may concern:

'Telegraph Receiving Devices, of which the following isaspecification. I My present invention relates to electroreceptive devices for wireless or space teleg-' raphy systems, and more particularly to' such devices as depend for their operation upon "the principle of the bolometer, which has for 1 long been known and used as ameans for do? tectingand measuring radiant energy. In the bolometer as used by Professor Langley thechange of electrical resistance of a conductor with temperature is employed to detect and measure the distribution ofhe'at in the solar spectrum, andthe development which this instrument has received at his hands, has made it a far more sensitive instrufnent even than the thermopile both for the detection and measurement of exceedingly feeble radiation This instrument has been -fso completely described in the scientific writ- 'ings of Professor Langley andothers that I need nottake the space here to describe the instrument in itsvarious forms and in its de- "tails of construction. 'a bibliograph'y'in which the theory, construction, and s'ensitiveness of the instrument is Suffice it to quote here finore if-u lly discussed than would be practica- "ble' in a patent specification.

"Bihlio'grap hyof the holometer. Svanburg,

Pogg. Ann., Vol.- XXIV, page 416, year 1851; Langley, Proceedings of the American 'ilfeteorological Society, December 23, 1880; Langle Proceedings of the American Acadj'eniy of Arts and Sciences, January 12, 1881,

IVol. Camb. Langley, American Journal f Science, Third SeriesV0L 21, No. 123, March,

1881; Langley, Ooniptes Rendus des Seances de l Academic des Sciences, Paris, September 11, 1882; Langley, American Journal of Sci enc'e, Vol. 25, March, 1883; Langley, Memoir,

enamel Academy of Sciences, April, 1883;

Langley "0fessional Papers of the Signal Serciee, No. 15, War Department, December 21, 1883; Langley, Proceedings of the Anieri Serial No. 119,211. (No model.) v i can Associaticnfor the Adoemcenient of Sci- 4 Part .2, Third Memoir, l Vashington, No-

vember, 1887; Langley, American Journal 0 f Science, Vol. 40, August, 1890; Langley, Annals o f the Astrophysical Ohsercatory of the Smithsom'cm Institution, Vol. 1, 1900; B. F.

Snow, T he Infra-red Spectra of theAl/talies; Physical Review, ,1, page 28, 1893; H. F.

Reid, Ph. D. Theory of the Boloineter; Aineri can Journal '0 7 Science, Third Series, 35, page 160, 1888; O. Lummer and F Kurlbaum, 'Wid. Ann, 46, pages A-to 224, 1892; Baur, Pro'c. Berlin Phys. Soc, March 3, 1882;

Baur, Ann. der Ph. und 0h., Vol. XIX, page 12, 1881. Besides the use of the instrument for detecting radiant energy in the form of heatwaves the, bolometer has been applied to the measurement of dielectric constants and to the detection and measurement of ordinary electromagnetic radiation, ,such as Hertz waves. (See Tachqlieeff, Journal de la Societe Physico- Ohemigue Russ, page 115, 1890.

Also Rubens, Paalzow, Ritter, Arons, lVied.

Ann. 37, page 529,1889; 40, page 55, 1890; 42, page 154, page 581; 44:, page 206. Also St. John Proc. Am. Acad. May 9, 18941.)

When the bolometer is to be used to detect electromagnetic radiations ofwave lengthsgreat compared to those of radiant heatthe electromagnetic waves are caused to develop a'current in the bolometer wire or strip. The energy thereby converted intoheat in the bolometer wire or strip raises its temperature, thereby increasing its resistance and unbalancing the bridge or induction balance of which it forms a part. 7

When the bolometer is to be used as a sigthat it be quick'to respond to the signals that the thermal time constant of the bolometer pal-receiving device, it is necessary in order wire or strip should be small, and for this reason the material of which the bolometer wire orstrip is composed should be of smallspecific heat and that the wire or strip should be of" small mass. It is also desirable for this purpose that the heat insulation of the wire or strip be not too perfect. In order to gain great sensitiveness, it is desirable that the bolometer wire or strip should be of a material having high specific resistance, a large resistance temperature coefiicient, and a small specific heat.

An extended list of specific heats may be found in PiWsz'kaZsc/r- Chemise/2.0 Tabellea by .Lcmdolt and Bomstcin, Julius Springer, Berlin, 1883. Avlist of the specific resistances and resistance temperature coeflicients may be found in Mathiessens Tables. From these tables it will be seen that bismuth is superior to other of the commoner metals for the purpose of the bolometer wire or strip, owing to its high specific resistance, high-resistance temperature coei'licient, and-low specific heat.

It is an inconvenient material to use, however, owing to its mechanical properties, being of small ductility and malleability. For this reason it is diflicult to construct in fine wire or excessively thin strips for thepurposes of the bolometer. For these reasons iron and platinum have been employed, When from the other considerations bismuth would have been preferable, and a truly remarkable degree of sensitiveness has been obtained.

ter as an electric translating device'in awireless-telegraph system is illustrated in Figure 1 of the drawings; but this method is not the preferred method, owing to the fact that in general the oscillatory current developed in the elevated conductor at a receiving-station is ofslnall amplitude of strength, and unless the resistance of the bolometer fine wire or strips be excessively great but a small amount of energy will be'dissipated in them. The response of the instrument to the signal-waves will therefore be under these conditions relatively feeble and the rate at which the instrument can receive signals will be relatively slow. The method and apparatus shown in this drawing is, in fact, identical with the method and apparatus published by Rubens, Ritt'er, and others.

In order to adapt the bolometer to properly perform the functions of a receiving instrument for wireless-telegraph systems, it is necessary to so arrange the apparatus as to amplify the oscillatory current in the bolometer fine wire or strips, and means for accomplishing this end are diagrammatically illustrated in Figs. 2 and 3.

Having given references to such printed publications as will serve to instruct those wishing to construct and operate the bolom: eter as a means of detecting and measuring the oscillations which occur in Wireless telegraphy, my invention may best be described by having reference to the drawings which accompany and form a part of this specifica- HOD.

Similar letters of reference have, so far as may be, been employed to designate similar parts throughout the drawingsoi this specification.

Fig. 1 illustrates diagrammatically the llubens apparatus for detecting electrical oscillations. Fig. 2 illustrates a modification of the Rubens apparatus for detecting electrical oscillations, especially adapting it to perform the functions of an electroreeeptive device in a wireless-telegraph system. Fig. 3 illustrates an induction-balance operating upon the bolometer principle and having such modifications as to be especially adapted to operate as an electroreceptive device for Wireless-telegraph systems.

V represents an elevated comluetor, preferably vertically elevated.

G represents a galvanometer or other suitable electric translating device.

R and R represent resistances.

B represents a battery or other suitable source of current adapted to operate the. electric translating device G. Thus if (1 l i a. galvanometer B must be a source of direct or unidirectional current, while if G be an electrodynamomctcr B must be a source. of either unidirectional or vibratory currents, and if G be ajtelephone B must be a source of rapidly-varying currents.

D is a source of rapidly-varying currents.

a a a a and 7) b 7/ 7/ are bolometer line wires or strips adapted to be heated by the passage of a small current.

E is an earth connection.

T is a telephone-receiver.

L is an inductance-coil.

L is a coil of inductance great as compared with the inductances of coil L.

C is a condenser.

The operation of Fig. l is the same as that of the Rubens device. In the normal adjustment of the apparatus the branches B and (l are conjugate, and there is, therefore, normally no current passing through (i. Moreover, if we designate the resistance of the several conductors a a, &c., b 7), &c., by their letters of reference their normal adjustment is: a a a :a/, fl, V II, 1/": a, 7/ a. The preferred :uljustment of the resistances of the branches a a, &c., l b, &c., is: (0 a e b b /W b, or, in other words, the resistances are all equal. In the reception of signals an oscillatory current is developed in the elevated conductor or oscillatorVE,and this current passing through resistance of these conductors, and this rise. in

resistance unbalances the Christi balance or Wheatstones bridge, of whlch these conductors form a part. A current is therehv caused to traverse the electric translating device (i,

which either indicates the passage of said current directly or by the closing of a local circuit adapted to operate a telegraphic sounder or recorder.

The organization shown in'Fig. 2 is identical with that shown in'Fig. 1, except that the bolometer fine wire or strips a a a" a form part of a resonant circuit a a a a L L C, attuned to the frequency of the electromagnetic signal-waves to be received. By this means the oscillatory currents developed in the conductors a a a a are not only much amplified when the signal-waves are of the frequency to which the circuit a, a, a c L L (J is attuned, but the organization is rendered selective, so that it is moreresponsive or sensitive to waves of this particular frequency than waves of any other frequency.

The organization shown in Fig. 3 is given in this specification merely to illustrate how varied may be the forms of induction balances or bridges employed without departing from the present. invention. In this arrangement of the apparatus, M is an induction coil or transformer, of which I and I are two exactly equal primaries, forming, in fact, a continuous coil and having a terminal brought out at the neutral point 0. By this construction the circuits containing the telephone-receiver T and generator D are normally rendered conjugate bymaking a a a" a b l): 6? 6". Under these circumstances no sound is heard in the telephone; but when signal-waves are received which correspond in frequency with the frequency to which the circuit a 6/ a a C L L is made resonant the inductionbalance is unbalanced and the telephone T gives forth a sound-signal. It is obvious that B and G may interchange positions without affecting the operation of the organizations, shown in Figs. 1 and 2, and it is also true that D and T may interchange positions in'Fig. 3 without affecting the operation of the apparatus.

I do not herein claim the method of receiving space-telegraph signals by utilizing the dissipative energy of the electric currents developed in an electroreceptive device by electromagnetic signal-waves, such method having been claimed in my application, Serial No.

122,853, filed September 10, 1902..

By the term dissipative energy I desire to be understood as meaning that part of the energy supplied to a circuit which is used in heating the conductors and which is thus dissipated into heat or, in other words, the product of that part of the applied electromotive force which is necessary to overcome thedissipative resistance R of the circuit and which is viz., the product R d 2 dt.

p maximum value of the current flowing ihlhe circuit. This'matter is more fully explained in my Letters Patent No. 7 87 ,17 0, dated August 25, 1903.

The specialforms of bridges and inductionbalances which may be used for the purpose and in the manner hereinbefore described are very great, and some of these forms are well known in the arts. I therefore wish it to be particularly understood that I do not restrict myself to any special form of bridge or balance" or mode of associating a bolometer fine wire or stripwith such bridge or balance; but

I claim, broadly, as myinvention 1. ,In a bolometer for detecting oscillatory currents, a resonant circuit, comprising the fine wire or strip of said bolometer and attuned to the frequency of the oscillatory current to be detected.

2. In a system of space telegraphy, an electroreceptive device comprising a bolometer, and a' resonant circuit, including the fine wire or strip of said bolometer, attuned to the frequency of the electromagneticsignal-waves to be received.

3. In a system of spaceteleg raphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and includingan electroreceptive device comprising a conductor or a plurality of conductors of small specific heat and small mass.

4. Ina system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device comprising a conductor or a plurality of conductors of small specific heat, high specific resistance, large resistancetemperature coefiicient, imperfect heat insulation and small mass.

5. In a system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device comprising a conductor or a plurality of conductors of small thermal time constant.

6. In a system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device comprising a conductor or a plurality of conductors of small specific heat, imperfect heat insulation and small mass. l

7. In a system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device comprising means rapidly responsive as. regards temperature to Variations in the amplitudes of the electric currents developed in said resonant circuit.

8. A space-telegraph receiving system comprising a circuit attuned by capacity and indu'ctance to the frequency of the transmitted electromagnetic signal-waves and including means rapidly responsive as regards temperature to variations in the amplitudes of the electrical oscillations developed by said electromagnetic signal-waves in said circuit.

9. In a system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device comprising a member adapted by changes in its dissipative resistan'ceto produce indications in a suitable indicating device.

10. In a system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device comprising means adapted to transform the energy of the electric oscillations developed in said resonant circuit into thermal energy and thereby produce intelligible signals in a suitable indicating device.

11. In asystem of space telegraphy, an electroreceptive device comprising an inductionbalance, one branch of which includes a conductor or a plurality of conductors of small thermal time constant forming part of a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves.

12. In a system of space telegraphy, an elec troreceptive device comprising an inductionbalance, one branch of which includes a conductor or a plurality of conductors of small thermal time constant forming part of a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves, in combination With a source of rapidly-varying current and an indicating device, connected respectively in the normally conjugate branches of said induction-balance.

18. In a system of space telegraphy, a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves, in combination with an electric translating device adapted to utilize in its operation the dissipative energy of the electric currents developed in said resonant circuit.

14:. In a system of space telegraphy, a resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device adapted to utilize in its operation the dissipative energy of the electrical oscillations developed by said electromagnetic signal-waves in said resonant circuit.

15. In a space-telegraph receiving system, a circuit attuned by capacity and inductance to the frequency of the transmitted electromagnetic signal-waves and including an electroreceptive device adapted to utilize in its operation the dissipative energy of the electrical oscillations developed by said electromagnetic signal-waves insaid circuit.

16. In a system of space telegraphy, a receiving conductor adapted to have electric oscillations developed therein by means of electromagnetic signal-waves, in combination with a member of small thermal time constant adapted by the changes effected in its dissipative resistance by said electric oscillations to produce intelligible signals in a suitable indicating device.

17. A receiver for space-telegraph signals, comprising a sensitive member of small mass, small specific heat and imperfect heat insulation.

18. In a receiver for s 'iace-telegraph signals, a sensitive member of small mass, small specific heat and imperfect heat insulation, in combination with a signal-indicating device.

19. In a space-telegraph receiving system, a resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including a sensitive element of small thermal time constant.

20. In a space-telegraph receiving system, a circuit attuned by capacity and inductance to the frequency of the transmitted electromag netic signal-waves and including a sensitive element of small thermal time constant.

21. In a space-telegraph receiving apparatus, an electroreceptive device comprising a sensitive element of small thermal time constant and a source of vibratory currents associated therewith in combination with a signalindicating device.

22. In a space-telegraph receiving apparatus, an electroreceptive device comprising a sensitive element of small thermal time constant and a source of rapidly-varying currents associated therewith in combination with a signal-indicating device.

28. In a space-telegraph receiving apparatus, an electroreceptive device adapted to utilize in its operation the dissipative energy of the electrical oscillations developed by electromagnetic waves in the circuit in which it is included, in combination with a recorder.

24L. In a receiving apparatus for space-telegraph signals, a circuit including a source of electrical energy, an indicating device, and a sensitive element adapted by changes in its dissipative resistance to produce indications in said indicating device.

25. In a receiving apparatus for space-telegraph signals, a circuit including a source of electrical energy, an indicating device, and a sensitive element adapted to utilize the dissi patii e energy of the electrical oscillations passing through said element to produce current variations in said circuit.

26. A receiver for space-telegraph signals comprising a sensitive element adapted to utilize in its operation the dissipative energy of the electrical oscillations developed by electromagnetic waves in the circuit in which said sensitive element is included.

27. A receiver for space-telegraph signals comprising a sensitive element adapted to utilize in its operation the dissipative energy of the electrical oscillations developed by electromagnetic waves in the circuit in which said sensitive element is included, in combination with a signal-indicating device.

28. In a system of space telegraphy, the combinatlon of a signal-indicating device and an electroreceptive device, said electroreceptive device comprising a sensitive element comprising a sensitive element of small mass and small specific heat and adapted to be 7 heated by the oscillatory electric currents developed by electromagnetic waves in the cir cuit in which said receiver is, lncluded.v

30. A receiver for space-telegraph signals comprising a sensitive element of smallinass cuit in which said receiver is included, in combination with a signal-indicating device.

31. A, space telegraph receiving system comprising a circuit attuned by capacity and inductance to the frequency of the transmitted electromagnetic signal-waves and including a sensitive element which is rapidly responslve regards temperature to the oscillatory electric currents developed by said electromagnetic signal-waves in said circuit.

32. A space telegraph receiving system comprising a closed resonant circuit attuned to the frequency of the transmitted electromag- I netic signal-waves and including a sensitive element which is .rapidly responsive as regards temperature to the oscillatory electric currents developed by said electromagnetic signal-waves in said resonant circuit.

33. A receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted to be heated by the oscillatory electric currents developed by electromagnetic signal-waves in the cir-, cuit in which said receiver is included.

34. A-receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted to be heated by the oscillatory electric currents developed by electromagnetic signal-waves in the circuit in which said receiver is included, in combination with a signal-indicating device.

35. In a space-telegraph receiving system, an elevated receiving-conductorv adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a receiver for space-telegraph signals comprising a sensitive element of small mass and small specific heat and adapted to be heated by oscillatory electric currents or electrical oscillations developed by electromagnetic signal-waves in the circuit in which said.

. receiver is included.

tion with a sensitive element of small .mass and small specific heat and adapted to be heated by the oscillatory electric currents developed by electromagnetic signal-waves in the circuit inwhich said receiver is included,

and a signal-indicating device associated with said receiver.

37. In a space-telegraph receiving system,

an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-Waves, in combination with a circuit attuned by capacity and inductance to the frequency of the transmit ted electromagnetic signal-waves and including a sensitive element which is rapidly responsive as regards temperature to the oscillatory electric currents developed by said electromagnetic signal-waves in said circuit.

38. In a space-telegraph receiving system, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a closed resonant circuit attuned to the frequency of the transmitted electromagnetic signal-waves and including a sensitive element which is rapidly responsive as. regards temperature to the oscillatory electric currents developed by said electromagnetic signal-waves in said resonant circuit.

89. In a space-telegraph receivingsystem, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted to beheated by the oscillatory electric currents developed .by electromagnetic signal-waves in the circuit in which said receiver is included.

40. In a space-telegraph receiving system, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted to be heated by the oscillatory electric currents developed by electromagnetic signal-waves in the circuit in which said receiver is included, and a signal-indicating device associated with said receiver. v

A1. A receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted to transform the energy of the electrical oscillations developed by electromagnetic signal-waves in the circuit inwhich it is included into thermal n y- 42. In a space-telegraph receiving system, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted totransform the energy of the electrical oscillations developed by electromagnetic signal-waves in the circuit in which it is included into thermal energy.

48. A'receiver for space-telegraph signals comprising a sensitive element of small thermal time-constant and adapted to transform the energy of the electrical oscillations developed by electromagnetic signal-waves in the circuit in which it is included into thermal energy, and a signal-indicating device associated with said receiver.

44. In a space-telegraph receiving system, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a receiver for space-telegraph signals comprising a sensitive element of small thermal time constant and adapted to transform the energy of the electrical oscillations developed by electromagnetic signal-waves in the circuit in which it is included into thermal energy, and a signal-indicating device associated with said receiver.

45. A receiver for space-telegraph signals comprising a sensitive element adapted by the changes effected in its dissipative resistance by the energy of electromagnetic signal-waves to produce indications in a suitable signal-indicating device.

&6. In a space-telegraph receiving system, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a sensitive element adapted by the changes effected in its dissipative resistance by oscillatory electric currents to produce indications in a suitable signal-indicating device.

47. In a space-telegraph receiving system, the combination of a signal-indicating device and an electroreceptive-device, said electroreceptive device comprising a sensitive element adapted to be heated by the oscillatory electric currents developed in the circuit in which it is included and to thereby control said signal-indicating device.

48. In a space-telegraph receiving system, an elevated receiving-conductor adapted to have electrical oscillations developed therein by electromagnetic signal-waves, in combination with a signal-indicating device and an electroreeeptive device, said electroreceptive device comprising asensitive elementadapted to be heated by the oscillatory electric currents developed in the circuit in which it is included and to thereby control said signalindicating device.

In testimony whereof Ihavc hereunto subscribed my name this 9th day ()1 August. 1902.

JOHN S"ONE SIONE.

itnesses:

ELLEN B. TOMLINSON, J EREMIAII TOOMEY. 

